The stage of a cancer is how much cancer there is and how far it has spread in your body. Your healthcare provider uses scans and tests to find out the size of the cancer and where it is. Scans can also show if the cancer has grown into nearby areas and if it has spread to other parts of your body.
The grade refers to how the cancer cells look when compared to normal kidney cells. The grade of your cancer will help your healthcare provider predict how fast the cancer may grow and spread. A scale of 1 to 4 is used to grade kidney cancer. The lower the number, the more the cancer cells look like normal cells. These cancer cells tend to grow and spread slowly. This means the cancer might be easier to treat and cure. Grade 4 cancer cells look very different from normal kidney cells. This grade of cancer is harder to treat.
Staging and grading of cancer is important for deciding how to treat it and whether it can be cured.
The most commonly used system to stage kidney cancer is the TNM system from the American Joint Committee on Cancer (AJCC). Be sure to ask your healthcare provider to explain the stage of your cancer to you in a way you can understand.
The first step in staging is to find the value for each part of the TNM system. Here's what the letters stand for in the TNM system:
T tells how far the main (primary) tumor has spread inside your kidney and into nearby tissue.
N tells if the lymph nodes near the primary tumor have cancer in them.
M tells if the cancer has spread ( metastasized) to distant organs in the body, like the liver, lung, bones, or brain.
Numbers or letters after T, N, and M provide more details about each of these factors. There are also 2 other values that can be assigned:
X means the provider does not have enough information to tell the extent of the main tumor (TX), or if the lymph nodes have cancer cells in them (NX).
0 means no sign of cancer, such as no sign of spread to the lymph nodes (N0).
The T, N, and M values from the TNM system are used to put these cancers into stage groupings. The groupings give an overall description of your cancer. A stage grouping is listed as a Roman numeral and can have a value of I (1), II (2), III (3), or IV (4). The higher the number, the more advanced the cancer is. Letters and numbers can be used after the Roman numeral to give more details.
These are the stage groupings of kidney cancer and what they mean:
Stage I. The cancer is only in the kidney. It's 7 centimeters (cm) (about 2.75 inches) or less across.
Stage II. The cancer is only in the kidney. The tumor is more than 7 cm across.
Stage III. The cancer is any size, it hasn't spread to distant parts of the body, and one of the following is true:
The cancer may have spread outside the kidney, but it hasn't spread beyond Gerota’s fascia (a thin sac that covers the adrenal gland and kidney). It has spread to nearby lymph nodes but not to other organs or tissues near the kidney.
Cancer has grown into a large vein or into nearby tissue, but it's not in the adrenal gland or beyond Gerota's fascia. It has not spread to any lymph nodes.
Stage IV. One of the following is true:
The cancer has spread outside Gerota's fascia (a thin sac that covers the adrenal gland and kidney). It may have spread to the adrenal gland on top of the kidney. It may or may not be in nearby lymph nodes. It has not spread to distant lymph nodes or organs in other parts of the body.
The cancer has grown outside the kidney. It may or may not be in nearby lymph nodes. It has spread to distant lymph nodes or other organs, like the bones, liver, brain, or lungs.
Once your cancer is staged, talk with your healthcare provider about what the stage means for you. Make sure to ask questions and talk about your concerns.